Immense future potential of heat pumps with scandium oxide
Heat pumps are generally considered a technology for saving the climate. Nevertheless, according to wissenschaft.de, heat pumps and climate technology are responsible for 20% of global electricity consumption and thus also for almost 10% of worldwide greenhouse gas emissions. Researchers from the Luxembourg Institute of Science and Technology have now developed a solid-state heat pump that is significantly more environmentally friendly and efficient thanks to a new material containing scandium oxide.
Scandium oxide enables breakthrough in cooling technology
A heat pump essentially works like a refrigerator, only in reverse: instead of extracting heat from an interior space to cool the food stored there, it draws heat from the environment to heat an interior space, such as living areas. Until now, this technology has been based on relatively inefficient vapor-compression processes that use an environmentally harmful refrigerant. The electrocaloric solid-state heat pump developed by researchers in Luxembourg, by contrast, generates heat directly from electricity and therefore does not require a compressor or coolant. The secret behind the new heat pump’s high efficiency is a unique compound of lead, scandium oxide, and tantalate. This is a caloric material—i.e., a metal compound that changes its temperature in a magnetic or electric field or through mechanical deformation.
Will heat pumps soon become more environmentally friendly and efficient?
Lead–scandium oxide–tantalate heats up when electricity is passed through it and cools down when the power supply stops. To make energetic use of the temperature change, the researchers placed elements made of the material between two liquid circuits, one of which is heated and one cooled. In doing so, they observed truly remarkable efficiency gains: the caloric heat pump achieved 64% of the possible efficiency. Conventional heat pumps reach only 50% or 30% due to material limitations. The electrocaloric system also offers advantages over solid-state heat pumps based on magnetic fields or mechanical deformation. Because the current flows directly through the material, no additional devices are required to generate magnetic fields or apply mechanical force.
Scandium oxide indispensable for the energy and transport transition
Scandium oxide is an important commodity for the future, as this rare earth is used in many key technologies. As part of lightweight alloys, it plays an increasingly important role in automotive manufacturing, especially in China (as we reported).
Above all, however, large quantities of scandium oxide are needed for the production of green hydrogen, which is expected to significantly increase demand. An investment in this particular rare earth is therefore certainly worth considering.